Earlier quoted context omitted.
It's called logical addition which is different than arithmetic addition, so it's best to not conflate the two. It's called "addition" because you "add" another propostion, creating a disjunction. And by the rules of logic, as long as the original proposition was true, the truth value is preserved no matter how many propositions you introduce (or "add"). A ⊢ ((A ∨ B) ∨ C) ... ∨ n
> It's called "addition" because you "add" another propostion, creating a disjunction. By that argument, conjunction is also called "addition". Perhaps there's a different reason? The choice of terminology, contrasting "logical addition" with "logical multiplication", obviously indicates that logical addition is supposed to be analogous to addition. What is the analogy?
A chain of (arbitrary) conjunctions is not necessarily implied by the first proposition, so we have the much less interesting:
A ⊬ ((A ∧ B) ∧ C) ... ∧ n